Implemented the email recover command

src/main/java/fr/xephi/authme/command/CommandManager.java

@@ -5,6 +5,7 @@ import fr.xephi.authme.command.executable.authme.*;
 import fr.xephi.authme.command.executable.changepassword.ChangePasswordCommand;
 import fr.xephi.authme.command.executable.email.AddEmailCommand;
 import fr.xephi.authme.command.executable.email.ChangeEmailCommand;
+import fr.xephi.authme.command.executable.email.RecoverEmailCommand;
 import fr.xephi.authme.command.executable.login.LoginCommand;
 import fr.xephi.authme.command.executable.logout.LogoutCommand;
 
@@ -512,6 +513,20 @@ public class CommandManager {
         changeEmailCommand.addArgument(new CommandArgumentDescription("oldEmail", "Old email address", false));
         changeEmailCommand.addArgument(new CommandArgumentDescription("newEmail", "New email address", false));
 
+        // Register the recover command
+        CommandDescription recoverEmailCommand = new CommandDescription(
+                new RecoverEmailCommand(),
+                new ArrayList<String>() {{
+                    add("recover");
+                    add("recovery");
+                    add("recoveremail");
+                    add("recovermail");
+                }},
+                "Recover using E-mail",
+                "Recover your account using an E-mail address.",
+                emailBaseCommand);
+        recoverEmailCommand.addArgument(new CommandArgumentDescription("email", "Email address", false));
+
         // Register the help command
         CommandDescription emailHelpCommand = new CommandDescription(
                 new HelpCommand(),

src/main/java/fr/xephi/authme/command/executable/email/RecoverEmailCommand.java

@@ -0,0 +1,95 @@
+package fr.xephi.authme.command.executable.email;
+
+import fr.xephi.authme.AuthMe;
+import fr.xephi.authme.ConsoleLogger;
+import fr.xephi.authme.cache.auth.PlayerAuth;
+import fr.xephi.authme.cache.auth.PlayerCache;
+import fr.xephi.authme.command.CommandParts;
+import fr.xephi.authme.command.ExecutableCommand;
+import fr.xephi.authme.security.PasswordSecurity;
+import fr.xephi.authme.security.RandomString;
+import fr.xephi.authme.settings.Messages;
+import fr.xephi.authme.settings.Settings;
+import org.bukkit.command.CommandSender;
+import org.bukkit.entity.Player;
+
+import java.security.NoSuchAlgorithmException;
+
+public class RecoverEmailCommand extends ExecutableCommand {
+
+    /**
+     * Execute the command.
+     *
+     * @param sender The command sender.
+     * @param commandReference The command reference.
+     * @param commandArguments The command arguments.
+     *
+     * @return True if the command was executed successfully, false otherwise.
+     */
+    @Override
+    public boolean executeCommand(CommandSender sender, CommandParts commandReference, CommandParts commandArguments) {
+        // AuthMe plugin instance
+        final AuthMe plugin = AuthMe.getInstance();
+
+        // Messages instance
+        final Messages m = Messages.getInstance();
+
+        // Get the parameter values
+        String playerMail = commandArguments.get(0);
+
+        // Make sure the current command executor is a player
+        if(!(sender instanceof Player)) {
+            return true;
+        }
+
+        // Get the player instance and name
+        final Player player = (Player) sender;
+        final String playerName = player.getName();
+
+        // Command logic
+        if (plugin.mail == null) {
+            m.send(player, "error");
+            return true;
+        }
+        if (plugin.database.isAuthAvailable(playerName)) {
+            if (PlayerCache.getInstance().isAuthenticated(playerName)) {
+                m.send(player, "logged_in");
+                return true;
+            }
+            try {
+                RandomString rand = new RandomString(Settings.getRecoveryPassLength);
+                String thePass = rand.nextString();
+                String hashNew = PasswordSecurity.getHash(Settings.getPasswordHash, thePass, playerName);
+                PlayerAuth auth;
+                if (PlayerCache.getInstance().isAuthenticated(playerName)) {
+                    auth = PlayerCache.getInstance().getAuth(playerName);
+                } else if (plugin.database.isAuthAvailable(playerName)) {
+                    auth = plugin.database.getAuth(playerName);
+                } else {
+                    m.send(player, "unknown_user");
+                    return true;
+                }
+                if (Settings.getmailAccount.equals("") || Settings.getmailAccount.isEmpty()) {
+                    m.send(player, "error");
+                    return true;
+                }
+
+                if (!playerMail.equalsIgnoreCase(auth.getEmail()) || playerMail.equalsIgnoreCase("your@email.com") || auth.getEmail().equalsIgnoreCase("your@email.com")) {
+                    m.send(player, "email_invalid");
+                    return true;
+                }
+                auth.setHash(hashNew);
+                plugin.database.updatePassword(auth);
+                plugin.mail.main(auth, thePass);
+                m.send(player, "email_send");
+            } catch (NoSuchAlgorithmException | NoClassDefFoundError ex) {
+                ConsoleLogger.showError(ex.getMessage());
+                m.send(sender, "error");
+            }
+        } else {
+            m.send(player, "reg_email_msg");
+        }
+
+        return true;
+    }
+}